Fifty Shades of Green
by KaydenceRei
Summary: Tony is the only one who saw the growing relationship between Bruce and Natasha firsthand. Sometimes he found it utterly hilarious and other times it was frustratingly pathetic. (The growth of Bruce and Natasha from Tony's perspective. From beginning to end.)


**Disclaimer** : I'm not even allowed to own my taco. My cat stole it. Therefore... nothing here is my property. Oh well...

Written by request of **Black Victors' Cachat** and named for Tony's joke in my story **The Gray Areas** , "Well this is very Fifty Shades of Green and all". I swear this is NOT what you guys are thinking. It's not rated M for a reason, haha.

 **Fifty Shades of Green** :

When the other Avengers first started taking up residence inside the newly renovated toward, Tony didn't see any real difference in the man that he had sort of forced his friendship on. Bruce remained ever vigilant to either live in the lab with Tony himself or hide on his own floor, usually in his bedroom, just in case anybody happened to wander into his living space. While the scientist seemed perfectly content and even self-deprecatingly humorous in his own presence, he tended to clam up rather awkwardly in the presence of anyone else when he actually wound up in the same room.

Of course Tony prided himself on his keen observation skills, or as Pepper rather adorably preferred to say, his knack for invading people's privacy and nosing into their business. He noticed immediately that a certain redheaded assassin and spy was nearly as evasive and unsociable as Bruce was the first time that she showed up to stay in the tower. It was just after a mission with America's wonderboy and both of them looked like they had been through the ringer, covered in soot and grime when they arrived, and it seemed it had been Steve's idea to come to the tower. Natasha had looked like a rather unwilling follower as she trailed in behind the good Captain.

While Natasha had disappeared to the floor Tony had informed her was 'all hers', Steve had a rather kicked puppy expression to his face when he explained that she was apparently rather unhappy with their ordered partnership by one Nick Fury. By their appearances, Tony couldn't really blame her, it didn't exactly look like it went well. It seemed Natasha wasn't all that different from himself, she didn't play well with others unless it was an alien war, and she didn't seem keen on changing that.

It was later that night when he watched the _first_ of many odd interactions between the beauty and the dork. It wasn't a good one, but when it came to an assassin with rather robotic emotions and a scientist who was socially inept at best, he supposed it could have been much worse. She was robot Natasha. _Robotasha_.

Tony was sitting at the bar in the lounge and chatting with Bruce when Natasha wandered inside. She was cleaned up from when he saw her that morning and if he was honest, she looked like she was in desperate need of a drink.

"Hey Red, need a shot of vodka?"

She was stone-faced as she glanced between himself and Bruce, and he watched as Bruce tried to shrink and hide on the bar stool, a rather pathetic attempt to pretend like he wasn't there. Those impeccably green eyes were like little voids as they shifted again to lock onto the not-so-invisible scientist beside him. He supposed her spidey senses tingled, because she seemed to know just as well as he did that Bruce's reaction to her was a bit unlike the others. Sure, Bruce was quiet and awkward near anybody that wasn't Tony himself but he didn't try to _hide_.

Much to both Tony's relief and Bruce's, she made no mention of his friend's behavior, in fact Natasha seemed to think a slightly humorous response was the best way to proceed, something which Tony gave her props for. Her eyebrow quirked up ever so slightly as she returned her eyes to himself and she gave him a rather wry and forced smile, "There a reason you went with vodka over _every_ other possibility?"

"You're Russian, obviously," and he watched as Bruce gave him this absurdly offended look on Natasha's behalf, something which didn't go all that unnoticed by the said assassin. "Or you were," Tony tacked on playfully as he pulled a rather expensive bottle off the shelf and held it out in her direction.

She finally seemed to decide she would enter the lounge fully as she made her way towards them. It was then he got a good look at her face. There was a tiny cut along one eyebrow, her lip was split, and a skinny line of purplish blue marred it's way down from her temple to the tip of her cheekbone. If anything it seemed to bring Bruce out of his invisibility cloak as the scientist looked at it all with a bit of worry.

Natasha feigned ignorance to Bruce's extensive study of her face as she took the bottle in her grasp, twisted off the cap, then drank it straight up. She lowered the bottle from her lips and spoke, "Well, you made a decent if not valid assumption."

Tony couldn't help but to give an appreciative little whistle. "See?" he questioned as he nudged Bruce with his elbow, "Russian." He watched as Bruce huffed out a disbelieving little breath at his antics, but to the relief of them both, Natasha actually looked mildly amused. Of course at his next comment his friend quite literally facepalmed, "So what did you take to the face, Romanoff?"

Both of Natasha's eyebrows arched at the question and Bruce threw a chided warning at him, "Tony..." His friend gave Natasha a rather weary and apologetic expression on his behalf. "That's his sordid way of asking if you're okay..." came the quiet explanation.

"I'm fine." It came out a little curt and he watched as her eyes narrowed a little when Bruce looked away and fidgeted on his stool. Tony wasn't sure if it was Bruce's obvious discomfort with her not so pleasant response, or his clear worry over her injured face, or maybe it had to do with his blatant discomfort with her presence in general. Either way, she seemed to understand that Bruce was the type of person who needed more than a two word answer, and she actually gave one to Tony's question of what she took to the face, "It was an explosion. Pipe flew out from the pressure." She put her index finger on her temple and then Tony snickered at the sardonic little look she gave him, "I've taken worse to the face."

He hooted out a little laugh at the joke she cracked in the end and even Bruce gave an awkward little huff of a laugh.

"You know, Romanoff? You keep that up, I might just like you," he informed her.

There was the slightest roll of her eyes before one corner of her lips quirked just a little into a tiny smirk, "Well, with Dudley Do-Right glued to my ass, I suppose somebody else besides had to like my sense of humor while Barton's on vacation."

Tony watched as his friend actually managed to smile just a little at the comment.

"Anyways, I need to go write a report," she handed the bottle back to him before she headed for the doors.

"Try not to take anymore pipes to the face," he called out.

He watched Bruce chuckle when her hand rose over her shoulder and graced him a rather indecent gesture as she disappeared around the corner.

"What's your issue with her?" Tony finally dared to ask when he deemed her out of earshot.

He heard Bruce's worn out little sigh as his shoulder's sagged a little, "I almost killed her, you know, just in case you forgot."

Tony waved off that answer, "Please, Bruce. In case you forgot her conversation with Loki, Barton tried to kill her too, and she seems perfectly fine with him. And she seemed perfectly okay with you, too. Actually, I think she was trying to make you more comfortable, which is funny since she doesn't strike me as the type to usually bother with placation."

"Yeah... yeah I got that," his friend muttered with a shake of his head.

"Just checking."

And of course that didn't mean that Bruce would be instantly comfortable in her presence, and if Tony was right, Natasha wasn't all that comfortable in Bruce's either. She kept it pretty well-hidden in the week her and Steve stayed in the tower, but it became rather noticeable over the next few months. It was gradual, but she went from uptight and annoyed with most of the people around her to a little more loose-lipped and just a _slightly_ less annoyed.

There just wasn't much socialization between her and Bruce. She played nice with Steve, cracked the occasional joke with him, sparred in the gym with him. She was nice enough to Thor when he would visit, she even sparred with the Asgardian on occasion and Natasha seemed thoroughly happy that the demigod treated her as he would any other 'warrior'.

She was even pleasant enough around Tony himself, which he thought was weirdly fascinating, even when she gave him the middle finger on more than one occasion. He just considered it her endearing form of undying affection for him, something he told Bruce, which his friend found at least a little bit funny.

And Clint, well, her and Clint were just two weird little murdering and spying peas in a pod.

But as much as Bruce avoided her, he also noticed that Natasha covertly and expertly stayed out of the scientist's way as well. They never found their way into the same room without someone else inside as a buffer, never conversed with the other without prompting from someone else. It was all rather pathetic.

Months and not once did he find them alone. He knew Natasha was aware that Bruce avoided her like the plague, and he got the feeling that Bruce knew she was doing much the same.

It only changed after the Mandarin. After the Winter Soldier.

She didn't show up at the tower for a few weeks after SHIELD fell to HYDRA, and to be quite honest, it was a little disconcerting when he couldn't manage to get a location on her. For someone who had seemingly blown all of her covers, she knew how to hide, how to vanish.

He was heading for the kitchen on the thirtieth day since she had gone incommunicado when he heard voices. The quiet and worried voice of his best friend and the somewhat hollow voice of one lost then found assassin. Or was it former assassin?

Either way, he kept his distance and listened.

"How are you?"

"Fine," nearly the same curt response she had given him in their first interaction after New York, and just like that time, she seemed to remember who she was talking to, "Tired."

There was a bit of silence and Tony dared to glance in. Bruce was standing over the stove with a teapot and Natasha was sitting on the counter a few feet away, one leg tucked under her as the other hung off the side. He watched her ever vigilant eyes flicker almost imperceptibly to him when he saw Bruce hold a mug out to her, "Tea?"

The redhead blinked rapidly as she looked at the offered drink before she took it in her hands and moved her gaze back to Bruce, "Thanks."

His friend gave the tiniest nod before he poured a cup for himself. "If...you know, whatever you've been up to is making you so tired, maybe you should take a break," came Bruce's suggestion and Tony was glad his friend made it.

"Just tying up some loose ends that came out with all those files," she mentioned with an empty little smile.

"Loose ends from your own file?" was Bruce's rather blunt question and Tony found it rather surprising. His friend wasn't typically that blatant with his questions.

There was a small little nod as she sipped the tea. Tony figured that was another placation on her end given that he only ever bore witness to the redhead drinking coffee.

"Well... I'm sure Tony doesn't mind if you hide out here for a while. You don't really look like you've slept well in a while."

Bruce was right, he didn't mind at all, but he was also right that Natasha looked exhausted. He hadn't noticed it when he first looked at her, but there was the tiniest sag to her shoulders and a weariness to her eyes, it was almost unnoticeable if you weren't actually looking for it. Contrary to what most people thought, Bruce was a lot more perceptive than people gave him credit for. He might be socially awkward at best, but he understood inner demons, and it seemed he understood Natasha was suffering from a few.

"Always with one eye open."

"Well...you can close them both when you're here, Natasha."

Tony watched both corners of her lips curl up a little into a smile he hadn't seen her give anyone else before. It was simple and unforced, one of those smiles that just sort of happened unbidden, and if Tony had to define it he would merely call it _real_.

"Thanks, Bruce," it was about as genuine as he had ever heard her as she slipped off the counter and onto her feet. "Think I'll go do that..." and she handed him the cup, "Thanks for the tea."

"Anytime..."

Tony watched as she exited the kitchen and locked eyes with him for a moment and he just gave a little shrug, "Stay as long as you like."

Unlike with Bruce, she just gave a little nod and then walked away.

It seemed his quiet and awkward little friend had broken a barrier with Natasha after that first reappearance. Unlike their original stand-offish positions with each other, they no longer actively avoided each other, Natasha occasionally sought Bruce out. On rare occasions Tony found her just sitting in a chair in the lab while Bruce worked. There wasn't much talking, just a fascinatingly companionable silence.

If he had to explain them, they were a bit like two haunted and kindred spirits. It took Tony a long time to see that the same darkness that lurked behind Bruce's eyes, also lurked behind Natasha's. They were plagued by their own pasts, Bruce by his monster, Natasha by her demon.

He knew much of Bruce's past, some he found out with research, some from the man's own mouth. He also knew some of Natasha's from her SHIELD file, and while originally that was the reason why he disliked her, he realized that her past wasn't who she was just like Bruce's monster wasn't who he was.

Tony found he actually liked her once he looked passed all of blood that painted her life, more so when he saw Bruce smile at something she said to him.

Bruce rarely smiled at anyone, his laughs were even more unheard of, unless of course it was with Tony himself. It was a bit of a breath of fresh air to see him do it now, it just surprised him that it was with Natasha and it was equally as surprising that she did the same with Bruce.

Over another few weeks he realized that it was his best friend's dorky humor that seemed to remove more barriers and walls. Robotasha was long gone, replaced by Natasha, and Natasha was much more pleasant to be around.

There was, of course, the clumsiness of the first time he saw Natasha initiate physical contact.

It was in the lab once again while Tony himself was actually still in there. She had crept in, said hello, and placed a hand on Bruce's shoulder.

Bruce had jerked a little, knocking a rather potent liquid onto a powder that had a tendency to ignite and caused a small little explosion of black dust that covered the scientist's face. Tony had snorted a little and watched as Natasha retracted her hand while trying not to smile. His friend looked rather pathetic over it, blinking rapidly and rubbing at his face.

Just to add to Bruce's discomfort, Natasha had wandered away and reappeared moments later with a wet rag.

Tony was biting back a laugh at the rigidity of Bruce's posture the second the the redhead leaned forward and started wiping off the soot.

And it only got more hilarious from there.

Natasha seemed to decide it would be fun to see how much she could make his friend flounder for a few more weeks following that incident. He would catch sight of them every now and then.

Normally, Bruce wasn't all that clumsy at all, he was actually pretty well-balanced. Tony recognized the sudden onslaught of clumsiness for what it was.

Bruce had a crush on Natasha.

And Natasha was _well_ aware.

She would test boundaries with the the awkwardness that resulted any time she so much as batted a not-so-innocent eye at him. And Tony thought it was absolutely hilarious.

A lot of nights her and Bruce watched old movies together, something that his friend was always fond of, and Natasha had easily taken a liking to. And as her testing of boundaries went by, the space between the two was slowly evaporating, and Tony was positive that Bruce had absolutely no idea.

Night after night, week after week, she sat a fraction of a hair closer. For a man who noticed a _lot_ of things, he didn't seem to notice Natasha was getting closer until her thigh was practically burning heat against his own, and Tony walked in to see the scientist's face a very deep shade of red. Natasha paid absolutely no mind to it, watching the movie as though nothing at all had changed, but Tony saw the knowing little smile.

Next time Tony walked in to find her just as close with equally hilarious results. A very stiff and plank-like Bruce with one completely amused Natasha beside him. Each time he came across them, it was the same result, until slowly Bruce started to get comfortable with it.

That was another reason Tony had grown to like her more and more. She knew when a boundary needed to be waited out. She didn't push closer, not until Bruce had fully gotten used to her sitting so close to him, that was when Tony walked in to witness her casually lay her head down on Bruce's shoulder.

Bruce's head turned slightly and Tony watched as he blinked rapidly and stared down at her, and that was when Tony realized that maybe Natasha hadn't _purposely_ done it. Bruce proved that to be a valid thought. His friend noticed him in the doorway, raised his index finger to his lips and _shushed_ him.

Natasha had fallen asleep. All that work and she missed the one time Bruce didn't fumble the damned ball. Maybe it was the fact the she _wasn't_ aware that made him less clumsy, because Tony watched the man tug the blanket off the back of the couch and settle it over her. While Natasha's body just seemed to sink a little further onto Bruce with each passing second, he paid no mind to it, not even her head and one hand that rested on his chest.

Bruce's one arm simply draped over her as he stoically continued to watch the movie.

He came across that scenario more often, though sometimes Natasha was awake rather than asleep, and Bruce seemed to have acclimated to her close proximity.

 _Then_ she started the flirting.

Tony never laughed harder than the first time it happened.

The same kitchen where the two had first formed their little bond of friendship was where Natasha pushed the boundaries further. Bruce had cooked them all dinner, some dish that he learned to make in India.

"Remind me again what I'm about to die from?" Tony questioned. He witnessed a rather exaggerated eyeroll from Natasha across the table as she kicked his shin, "You play a rough game of footsies, Romanoff. That's not very nice."

Bruce gave the two of them a rather bemused look before he finally answered, "Piro Aloo."

"Pee on a who?" Tony grumbled out.

Bruce didn't bat an eye, "Piro Aloo."

"Can't we just order pizza?"

"No," came the perfectly in-sync answer from both Bruce and Natasha.

He huffed out a sigh at that.

"Get some water handy though... it's really hot."

And then Natasha bit off more than Bruce could chew.

"A little spice never hurt. I like a bit of heat..."

It was said in such a voice that Bruce fumbled endlessly with the wooden spoon in his hand before it clattered across the counter and Tony himself actually choked on his sip of water.

When Tony finally dared to look up, he could see her smirking into her coffee cup as Bruce's hands clumsily missed grasping the wooden spoon on several attempts. He actually had to fight with himself not to break into a fit of laughter when she looked up and fluttered a rather innocent look towards Tony beneath her eyelashes.

After that incident, he came across Natasha teaching the passive scientist self-defense moves on the gym's sparring mat. That was the _last_ thing he ever thought he would see.

And Natasha wasn't taking it easy on him.

Tony expected to see Bruce turn green the second she flipped him over her shoulder. Instead Bruce just laid on the mat with Natasha's legs kneeling on either side of his chest, taking a few breaths to get the wind back that she knocked out of him.

"Huh...well, this is all very Fifty Shades of Green."

He heard Bruce groan and cover his face at the remark while Natasha lithely got to her feet and released a tiny little laugh at the comment.

Then he witnessed the second flirtation.

"Rough can be fun, Stark. Right, Bruce?"

"Oh geez..." and Tony could see the red creeping over Bruce's face as his friend tried to hide further and sink into the mat like quicksand.

And a few days later Natasha dropped the bomb on Bruce in the lab.

She wanted to face down the 'Other Guy' as Bruce called him. Day after day, for a month, Bruce denied her request. Closed himself off from her and actively tried to avoid her again.

Tony was the one who had to get answers out of her. To try and understand why she wanted to do it. At first he thought that maybe that's what her whole play at this weird friendship she and Bruce had come upon was about. He was afraid she had been manipulating his friend for months just to get at this moment.

And he wasn't wrong, Natasha told him as much when he straight up asked the question.

"At first...yes," she answered. "I was manipulating him. I was pulling the strings..." she admitted without much shame. Tony hated her for all of thirty seconds until her next unexpected admittance, "It stopped being a game of manipulation a while ago, but that doesn't change anything."

He didn't hate her after that but he was definitely still a little pissed. "Then tell me why," he insisted as he folded his arms over his chest, "Tell me why it's so important that you played Bruce like a fiddle for all this time and I sincerely hope your answer actually has sound reasoning."

Natasha released the tiniest little breath of frustration as she rubbed at her eyes. Something about the reaction was just so _Bruce_ -like that he actually felt some of the anger at her dissipate. Before she ever answered he knew that it was just another demon inside her, chewing away, and she needed to smite it before it overwhelmed her.

"Natasha," and he tried his best to hide his annoyance with her, "Just tell me the truth."

Her eyes narrowed just slightly before she finally gave him the answer he wished she hadn't, "Because the Big Guy scares the hell out of me...he terrifies me." She looked away just slightly, like admitting to the fear was like showing some weakness, and he supposed to her it _was_ weakness. "I don't scare easy. First I thought that being friends with Bruce would help, you know?" she questioned. He gave the barest of nods at that. "It didn't work, but I like being his friend...and it's hard to do that when all I think about is the possibility he could and almost did smear me on a wall."

Tony wasn't sure why he never saw that, how she hid that for five months without ever giving away those feelings, and even now she spoke it all with a hollow voice. It was a shell of what he heard from her voice when she spent time with his best friend. The original intention may have been a lie, but the results weren't, and she really did seem to need this.

"I have to face it."

He frowned a little at that, but he understood it, he understood what she meant.

"I _want_ to be his friend, Tony...but I can't keep this up unless I face this head on."

"Alright...okay," he sighed as he rested his hand on the back of his neck, "I'll talk to him."

It was one of the few times her eyes ever softened for Tony himself, something that was surprising and equal parts frustrating; frustrating because it made the last of his anger with her simmer away, especially with her next words, "Thank you..."

The gratitude was genuine. "You know, I like it better when you give me the finger," he felt reasonably better when she smiled and flipped him the bird, "Yup, much better, but if you ever manipulate Bruce like that again...you won't be welcome here."

"Understood."

It took him a few days to get Bruce to agree to it and only because he finally explained to Bruce what Natasha had explained to him. The horrified look on Bruce's face when he realized Natasha was _afraid_ of him, or rather, his other half; it was something Tony wished he hadn't seen.

"That's why she has that—that weird look sometimes," Bruce heaved out as he leaned forward and covered his face.

"Weird look?" Tony dared to ask.

Bruce gave a haggard and weary little nod. "When she thought I wasn't paying attention...the mask always slipped a little. She would watch me, I just never understood what that look in her eyes was until now..."

 _Well, shit..._ It was never as so well hidden as Tony thought it had been, but Bruce always did seem to see things in Natasha that Tony himself couldn't. "Bruce, you like being her friend?" with the weary little nod he resigned himself to the fact that these two were pathetically hopeless, "Then let her do it."

"He could kill her."

"She's a spy, a lot of things could kill her," Tony reminded him. "Look, she didn't say what I'm about to say, but if your green alter-ego had tried to pancake me? I wouldn't be able to look at you without thinking at any moment you might snap...and then snap me. No offense."

Bruce was frozen at that, staring with panicked eyes at the revelation and very clearly wondering if Natasha hid those same ill-thoughts when she looked at him. She had never said whether or not she was scared of Bruce himself, but she hid things so thoroughly that it was impossible to know.

"I'm not afraid of _you_ , Bruce," came her interruption into the conversation.

His friend looked rather crestfallen as she moved into the room. "It's the same thing..." he insisted.

Tony watched carefully as Natasha gently gripped Bruce's chin in her hand and forced him to look her in the eye, "It's not. You're not him, just like he's not you." To Tony's surprise, Bruce actually looked like he believed her and she sealed the deal with the softest tone either of them ever heard from her, "I'm not afraid of you. You're my friend."

"You—you really want to do this?" Bruce relented with a wary look.

"I _need_ to do this."

Bruce gave her this uncertain little look before he finally answered again, "Okay...okay, but... but only with him on the other side of the Hulk tank. You stay _behind_ the glass."

Natasha nodded her agreement to that, "Okay."

It wasn't all that exciting. She stood on one side of the Hulk-Tank, Bruce transformed inside, and the Big Guy slammed around inside it like a child throwing a temper tantrum.

They did the same thing several times and each time Natasha stoically watched in silence as the Big Guy did his thing.

Then she came to Tony first, "I have an idea."

"An idea?"

She inclined her head a little and he was sort of afraid he wasn't going to like it. "Subliminal messaging. I know what you said... about manipulation," she reminded him quickly. "But this one isn't for me... this one is for Bruce."

"For Bruce? How does subliminal messaging work _for_ Bruce?"

She shook her head, "It makes more sense when you're me, I guess." Natasha scrunched her nose up a little as she tried to think of a way to word it. "Okay...you've read my file, you know about Red Room," and he nodded. "They had techniques. They force you into one persona, make you fully believe you're that person until you finish the job. But eventually, you finish, and you need to be pulled out."

"Alright..."

"What if we could pull Bruce back out of The Hulk?" came her question.

Tony stared at her for a moment. "Wait... you want to—"

"I want to help him get some form of control. I want to help. One word, or even a touch... that was all it ever took for Red Room to turn us back into empty shells."

It sounded sincere, even if she was offering to do it in such a Natasha-esque way, a way he told her never to do again. "Manipulate Bruce, _again_..."

"Not Bruce."

He guffawed at that a little. "Let me...make sure I have this right. You want to manipulate _The Hulk_?"

"Yeah."

"Good God... you're insane, you know that?" he questioned as he sighed. Natasha gave him the finger and he chuckled, "Loathed as I am to admit it, I like it...but you need to tell Bruce. He has to agree."

She nodded at that.

He wasn't around for that conversation but Bruce didn't agree to it for another two weeks. Even when they started the effort, it took several months and a _lot_ of bruising on Natasha's end. The Big Guy didn't enjoy it.

And over those months, he watched that friendship between them grow further, watched as Natasha _touched_ , and _flirted_ , and _pushed_ Bruce more and more.

And sometimes... Bruce pushed back.

Probably one of the most hilarious moments he ever witnessed was when Bruce flirted with her first. It was by far the cheesiest moment that his best friend ever had and Tony actually felt just a little bit of pride.

For whatever reason, when Natasha returned from one of her random trips away from the tower, she was in a _mood_ like no other. She wasn't her normally friendly self, not even with Bruce, but the scientist seemed to have no issue with it.

Bruce was rattling off on his and Tony's latest pet project, and while normally Natasha feigned interest and understanding, today she just looked bored. "You really need a second hobby, Bruce," was her offhanded comment as she sat at the desk with her elbow leaning on it and her cheek resting in the palm of her hand.

There was no hesitation, no fear, no stuttering or stammering. Bruce just whipped out the comment like it was nothing, completely nonchalant, "Spending time with you _is_ my second hobby and you're in the my first hobby right now. Two birds, one stone."

Tony flicked his eyes from Bruce to Natasha almost immediately and she was staring at Bruce, stunned, and her lips were parted ever so slightly. That stunned look slowly faded as her eyes twinkled just slightly, then her lips curled into slanted little smile, "Dork."

Bruce just grinned at her retort and all Tony could do was shake his head.

It was like watching a bit of a train wreck sometimes. Natasha wasn't exactly subtle when she flirted and Bruce seemed oblivious to the fact she seemed to honestly be interested.

Even when 'The Lullaby' was fully in effect, able to be used outside of a contained environment and after the heat of battle, Bruce still never seemed to catch on.

While most things about Natasha, Bruce could see right through, this was one thing his best friend seemed pathetically and frustratingly inclined to ignore. Natasha even seemed to be a little at odds sometimes with her attempts and sometimes she would just huff out a little sigh and not bother again for a while.

So Tony finally intervened, afraid Natasha might just give up on the idea altogether. The truth was, she brought out a different side of Bruce that Tony had grown rather fond of. Funnier, more sociable, less self-hatred. He wanted his best friend to acknowledge her interest for somewhat selfish reasons really, but he wanted it for Bruce as well, and even a little for Natasha.

He found Bruce before whatever weird little thing between them dwindled to _only_ friendship, because really, Natasha was good for him...and Bruce was good for Natasha. He really didn't want Robotasha back.

"Bruce."

"Hm?"

He watched as Bruce looked up from the microscope in the lab and blinked a few times at him before Tony finally blurted it out, "You do realize Natasha likes you, right?"

"Friends like each other," Bruce reminded him with a roll of his eyes.

"Do we need to discuss how to know when a woman likes you as _more_ than a friend?" he asked dryly.

He watched Bruce blink a few more times before he frowned. "I know..."

"You know... wait you—you know?" Tony questioned, staring at him in utter disbelief.

Bruce gave a rather sheepish nod.

"And...you're not interested?"

"Of course I am..." Bruce murmured as he rubbed at his eyes, "but it can't work."

Tony frowned a little at that, "Why?" The man before him just gave him that self-loathing look and Tony sighed, "You're going to let that hold you back from this? You do realize that you're probably hurting her feelings every time you treat her growing interest like a joke, right?"

Bruce looked a little grief-stricken at that, "Hadn't really thought about that..."

"Did you notice she's showing that interest less and less?"

This time Bruce nodded.

"Maybe you should decide whether or not you want that interest to really fade... you might miss it when it's gone. If you don't... might be a good idea to flirt back. To show her."

It seemed Bruce came to that decision after that battle. Tony saw when Bruce went up to the bar, saw him say something that seemed to momentarily surprise the redhead mixing herself a cocktail, and Tony realized what that decision was.

Bruce flirted.

And Natasha flirted back in such a way that Bruce actually went back to floundering a little, to stammering out responses, and Tony just chuckled from a distance. Something she said turned Bruce's cheeks a little pink as he looked down almost embarrassed, and then whatever she said next made him look up with even more color.

Natasha didn't just flirt. She openly flirted, openly showed _more_ interest in Bruce at a _party_. And when she winked at Bruce and walked away, Tony moved closer but never made it in time, Steve got there first.

And the fact that Steve, of all people, noticed Natasha's obvious interest in Bruce? That was even funnier than the first time Bruce flirted with Natasha.

Ultron ended the entire thing between the two of them before they ever got started. Something Tony blamed himself for entirely. Bruce's other half took off after the battle of Sokovia and Bruce himself didn't come back after. Even when he was talking to Steve and Thor, after Thor disappeared, Tony could see Natasha watching the walls in the upper window of the building.

She lost something too, as much as Tony himself, if he had to hazard a guess. When he was getting in the car he saw her looking out the window at him and he wondered if she blamed him too. He tried not to think about that when he got in the car and left.

The last thing he expected was to see her eating toast in the kitchen of his Malibu house two weeks later. The look on her face was a little Robotasha-esque and he hated himself a little more for that.

But it changed a little as she lifted her eyes to meet his.

Natasha didn't blame him. She blamed herself as much as he blamed himself. And neither of them seemed to blame each other.

He knew that for a fact when she finally spoke, "I lost one friend but I'm hoping you'll tell me I didn't lose two that day."

Tony heaved out a sigh before he gave her a sad little smile, "No...no you didn't."

Robotasha faded completely to Natasha again as her lips curled into an equally sad smile, "Okay."

"Okay..." he repeated.

Maybe Bruce would come back.

And maybe things could be more than just 'okay'.

 **()()**

 **Well, not sure that was my originally intended direction, but I ran with it.**


End file.
